It is no secret that Christopher Robin Milne, who inspired his father, author and playwright A.A. Milne, to invent the fantasy world of Winnie the Pooh and served as the model for his namesake character Christopher Robin, had a vexed relationship with his father’s much beloved creation. In fact, as an adult he wrote several autobiographical books, including The Enchanted Places (1974) and Path Through the Trees (1979), about his often bitter experience being at the center of an early 20th-century international popular culture explosion when he was just a child. As he later wrote, he felt that his father “had got where he was by climbing on my infant shoulders, that he had filched from me my good name and had left me with nothing but the empty fame of being his son.”

That “empty fame” is the subject of Simon Curtis’s Goodbye Christopher Robin, which is not nearly as dark and despondent as the above quote might suggest, but still has plenty of room for heartbreak, sadness, and the particularly sharp pangs of parental betrayal. The story follows the sometimes tortured life of A.A. Milne (Domhall Gleeson), his wife Daphne (Margot Robbie), and Christopher Robin (Will Tilston), who unlike the character in the book was usually called Billy. Billy spent little time with his parents, as Daphne was a socialite who frequently left their rural home near Ashdown Forest in East Sussex to mix and mingle in London and Milne was preoccupied with his writing and frequently tormented by post-traumatic stress from his experiences fighting in the trenches in World War I. Instead, Billy spent much of his childhood being looked after by Olive (Kelly Macdonald), a young nanny whose attention and care stands in contrast to his parents’ distractions and preoccupations, especially after the publication and worldwide popularity of the Pooh books.

The first half of the film belongs primarily to Milne, whom Gleeson plays as a distant soul whose horrific experiences in the trenches have left him psychologically scarred, which makes it difficult for him to connect with others. His wife Daphne comes close at times to being an outright villain, as she is both materialistic and self-centered, traits that make it even more difficult for Milne and later Billy to lead anything like a normal life. The publication of the Pooh books seem to please her most, as they bring in a steady stream of income and also elevate her and Milne’s social status through their world-wide popularity. Gleeson comes dangerously close at times to making Milne so closed off that he ceases to be a presence, but he brings him back at crucial moments so we see that his connection with Billy, however tenuous, is still genuine, even if it feels awkward, even forced, at times.

The second half of the film belongs more to Billy, as Milne and Daphne are absent for long stretches of time traveling and promoting the books. Will Tilston is bright-eyed and has the kind of round, plump face that you can’t help but equate with both innocence and jubilance, which is partially why the pains of the “empty fame” handed down by his father are so emotionally agonizing. One of the film’s most emotionally rending sequences (which is also, as it turns out, entirely fictionalized) involves Billy being taken by his parents to a department store where he learns just before the doors open that he has essentially been used in a promotion and someone has won the right to have lunch with “the real-life Christopher Robin.” After the Pooh books take off, Billy is acutely aware of his value in promoting their sales, which is why he comes to despise them, especially as a young man (Alex Lawther) whose experiences in various boarding schools reinforce his desire to get as far as possible from his fictional counterpart, which results in his enlisting and fighting in World War II.

Director Simon Curtis (Woman in Gold, My Week With Marilyn), working from a script by Frank Cottrell Boyce (Millions, The Railway Man) and Simon Vaughan (a television producer whose only other writing credit is for a 2004 TV movie about the Canadian black bear that partially inspired Winnie the Pooh), has a tricky balancing act to manage, as Goodbye Christopher Robin is, in many ways, a film founded on disillusionment, although he clearly doesn’t want the film itself to be disillusioning. As one would expect from a year-end “prestige film” of this sort, it is beautifully shot by cinematographer Ben Smithard (Belle, The Man Who Invented Christmas), and it has the required air of serious import. There is, however, a constant danger that the film will become too despondent in its depiction of a small boy learning over and over again that he is valued more as the inspiration for a fictional character, rather than a person in and of himself. Yet, Curtis manages to balance those darker moments with small bursts of optimism that cut through the clouds of shallow celebrity and suggest that Billy can eventually take control of and own his otherwise hijacked identity. Milne has his moment of reckoning with what he has done to his son, which explains why he only published two Pooh books (although there is no mention of how his creation came to be controlled by Disney, which perpetuated the world of Pooh far beyond what Milne could have done on his own). As a unique story about a father and son, Goodbye Christopher Robin has quite a bit to impart about the trauma of betrayal, but also the power of forgiveness.